This specification relates to locating a source of a wireless signal, for example, a radio frequency signal.
The Global Positioning System (GPS) is an example of a satellite-based system that provides position, navigation, and timing services for user devices. For example, the GPS system can be accessed by a GPS receiver in a hand-held device, such as a smartphone or a navigation instrument, to determine geographic coordinates of the hand-held device. The GPS receiver can obtain measurements of the distance between the GPS receiver and GPS satellites, and the distance measurements are used to determine the GPS receiver's location.